Primer metering apparatus for ammunition loading machines

ABSTRACT

AN AUTOMATIC LOADING APPARATUS FOR SMALL ARMS AMMUNITION INCLUDING A HORIZONTALLY AND CYCLICALLY DISPLACEABLE TRANSPORT MEMBER FOR METERING PRIMERS FROM A GRAVITY-FEED VERTICAL SUPPLY STACK TO A WORK STATION WHEREIN THE DRIVE MEANS FOR THE TRANSPORT MEMBER INCLUDES A SPRING FOR RESILIENTLY BIASING THE TRANSPORT MEMBER INTO ENGAGEMENT WITH A PROGRAMMING CAM DURING MOVEMENT TOWARD THE WORK STATION, WHICH CAM POSITIVELY DRIVES THE TRANSPORT MEMBER BACK TO THE SUPPLY. APPARATUS FOR VACUUM CLEANSING THE METERING AREA IS PROVIDED. AN AUTOMATIC POWER INTERRUPTION FEATURE IS PROVIDED WHEREBY THE DRIVE MOTOR POWER IS INTERRUPTED IN THE EVENT THE TRANSPORT MEMBER FAILS TO MOVE OUT OF THE PATH OF A SWITCH CARRIED BY AN UPPER PLATEN ASSEMBLY WHICH FORMS PART OF THE DRIVE MEANS.

' FeB. 6; 1973 R. A. LEICH' 3,71

PRIMER METERING APPARATUS FOR AMMUNITION LOADING MACHINES Filed May 13,1971 2 Sheets-Sheet 1 IN VENTOR zoerf .4 Lez'c ATM)! II IL Y",

Feb. 6, 1973 R. A. LEICH 3,714,860

PRIMER METERING APPARATUS FOR AMMUNITION LOADING MACHINES Filed May 13,1971 2 Sheets-Sheet 2 RESiET RELAY H5 A C INPUT 1/8 4 mil! Hm;

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ATTORNEY United States Patent 3,714,860 PRIMER IVIETERING APPARATUS FORAMMUNI- TION LOADING MACHINES Robert A. Leich, Sonthfield, Mich,assignor to Camdex Inc., Detroit, Mich. Filed May 13, 1971, Ser. No.142,955 Int. Cl. F42b 33/04 US. Cl. 8623 12 Claims ABSTRACT OF THEDISCLOSURE An automatic loading apparatus for small arms ammunitionincluding a horizontally and cyclically displaceable transport memberfor metering primers from a gravity-feed vertical supply stack to a workstation wherein the drive means for the transport member includes aspring for resiliently biasing the transport member into engagement witha programming cam during movement toward the work station, which campositively drives the transport member back to the supply. Apparatus forvacuum cleansing the metering area is provided. A11 automatic powerinterruption feature is provided whereby the drive motor power isinterrupted in the event the transport member fails to move out of thepath of a switch carried by an upper platen assembly which forms part ofthe drive means.

This invention relates to ammunition loading machines and particularlyto an improvement in such machines whereby the risk of a primerexplosion during loading operations is greatly reduced, if noteliminated.

In the loading of small arms ammunition, i.e., rifle, pistol, andshot-gun shells, it is necessary to assemble a primer and a cartridge orcasing as well as to fill the cartridge or casing with powder, shot, orlead and to suitably crimp or close the cartridge or casing to provide aclosed package. In reloading operations applied to previously-usedcartridges or casings, the additional step of removing the old primer isalso required.

The primer itself is a small cap or wafer which is filled with apercussion powder so that upon application of pressure by means of ahammer or firing pin, a small explosion occurs, this explosion beingefiective to trigger the ignition of the larger quantity of powder inthe shell itself, thus, producing the gaseous expansion which propelsthe shot or slug through the barrel of the gun. If, during such loadingoperations as are carried out by automatic loading machines, apositively driven machine element is caused to apply pressure to animproperly positioned primer, an explosion is likely to occur in theloading apparatus itself. This normally occurs only if a primer feedoperation, for example, fails to function properly or, in the case ofautomatic reloading apparatus, a spent primer is not properly removedfrom a cartridge being reloaded. The danger of a primer explosion in theloading apparatus is particularly acute where a vertical stack ofprimers is employed as a gravity fed supply to the machine. Under thesecircumstances, the explosion of one primer can easily trigger theexplosion of all primers in the supply, thus, giving rise to anexplosion of considerable proportions.

In accordance with the present invention, an improvement to automaticloading machines is realized, this improvement being such as to greatlyreduce, if not eliminate the possibility of primer explosions in theloading phases due to pressure being applied to a primer by a drivenmachine element, such as a metering member. This is accomplished bymeans of a primer transport member which operates to cyclicallytransport primers from a supply point to a work station and by improveddrive means for such transport member, this drive means being such as toresiliently urge the transport member toward the work station but topositively drive the member from the work station back toward thesupply. Accordingly, the resilient drive force is such that the presenceof a primer in a position which interferes with the transport membersimply causes the transport member to stall, thus, interrupting loadingmachine operation. This is to be contrasted to prior art machineswherein a transport member is positively driven from the supply point tothe work station, thus, creating the possibility of the application ofpositive and full machine pressure to a primer in a jamming position.

In accordance with another aspect of the invention, the possibilities ofan improper primer metering operation are substantially reduced byeliminating the possibility for the accumulation of foreign particles,such as dirt and excess primer powder, in the primer metering area. Inaccordance with a specific form of the invention as hereinafter setforth in detail, this is accomplished by providing a vertical receptacleaperture in a primer transport member which receptacle aperture isaligned in the primer pick up or acceptance position with a verticalsupply stack on one side and a small aperture in a support member on theother side. The small aperture in the support member is suitablyinterconnected with a vacuum pump for the purpose of causing an air flowthrough the transport member receptacle aperture and through theaperture in the support member, thus, clearing the area of foreignparticles, such as dirt and excess primer powder which might otherwisecollect in excess quantities over a substantial period of operation.

According to a still further aspect of the invention, power interruptcontrol means are provided for monitoring the displacement of a primertransport member such that in the event the transport member fails to bereplaced from a primer acceptance or supply position toward a workposition as a portion of the drive means having a synchronized programof displacement move toward a predetermined position, the motive powersource of the drive means is momentarily rendered inoperative. In theillustrative embodiment of the invention hereinafter set forth indetail, this is accomplished by means of a switch having an externalcontact-type control element carried by a vertically-displaceableassembly which drives and programs the displacements of a transverselydisplacing transport slide bar. The drive means includes a verticallydepending cam carried by the vertically displacing assembly to cause thetransport slide bar to move from a primer supply position to a workstation where the primer is normally discharged into an area for laterassembly with a cartridge or casing. If the transport slide bar fails todisplace from the supply position to the work station position as thevertically-displaceable assembly descends, the control element powerinterrupt switch moves into an interfering relationship with the slidebar, thus, opening a relay between an electrical line, for example, anda motor which acts as the motive power source for the drive means.

The various features and advantages of the invention will become moreapparent from a reading of the following description of an illustrativeembodiment of the invention. By way of general description, thisillustrative embodiment comprises a support surface in the form of alower platen across which shells, casings, or cartridges move in anincremental fashion between various work stations at which theaforementioned operations are automatically performed. In one of thesework stations a primer or percussion cap is caused to be inserted intothe cavity at the end of the cartridge shell or casing. These primersare placed in position for assembly by means of a transport member inthe form of a flat bar which displaces horizontally and cyclicallyacross the lower platen under the driving force of a motor and an upperplaten assembly which moves vertically and cyclically relative to thelower platen to perform many of the machine operations involved in aloading sequence. The upper platen carries a cam having a dog legprofile on at least one surface, this cam interacting with a follower onthe transport slide to program the horizontal motion of the slide and tosynchronize it with the vertical motion of the upper platen. The slidemoves between a first position in which a vertically-oriented receptacleor aperture is lined up with a vertically stacked primer supply, thus,to permit the lower-most primer to drop into the receptacle aperture,and a second position horizontally spaced from the first positionwherein the primer receptacle is lined up with a lower platen apertureor seat into which the primer is dropped for later assembly to acartridge shell or casing. The slide is urged forwardly by a springwhich, thus, provides a resilient drive tending to urge the slidefollower into constant contact with the cam surface. Thus, only theforce of the spring can be exerted on any primer which might be placedin an interfering relationship with the sliding transport member and thespring force is selected to be'less than that which would cause aspontaneous primer explosion. However, the cam follower arrangement issuch as to provide a positive drive of the transport slide back towardthe supply position. The receptacle-aperture in the slide when in thesupply position lines up with a vacuum fitting and an aperture in thelower platen which clears the supply area of excess primer powder whichmight otherwise build up to potentially explosive portions. In addition,dirt and other foreign particles are kept out of the transport slidereceptacle.

The following specification sets forth the illustrative embodiment infull detail and is to be taken with the accompanying drawings of which:

FIG. 1 is a front partial view of an automatic loading machine embodyingthe invention;

FIG. 2 is a schematic side view of a part of the macine of FIG. 1 in afirst position;

FIG. 3 is a schematic side view of a part of the machine of FIG. 1 in asecond position;

FIG. 4 is a rear view of another part of the machine of FIG. 1 showing adetail in a first position; and,

FIG. 5 is a rear view of the part from FIG. 4 in a second position.

Referring now to FIG. 1, there is shown an automatic ammunition loadingmachine comprising a base 11 supporting a lower platen 12 which definesa series of laterally spaced work stations at which various loadingoperations are progressively performed. A shuttle bar 62 is caused totravel a substantially rectangular path to carry the casings through thework stations in an incremental fashion. The operations performed ateach station are subassembly operations to be performed in a certainorder. The finished ammunition emerges from a chute 13.

The platen 12 carries guide pins 40 which define the vertical path oftravel of an upper platen assembly 38 which when reciprocally,vertically driven, effects several of the loading operations ashereinafter described. One of these operations is the metering ofprimers from a supply tube 26 to a work station directly in front of thetube 26, an operation best understood by reference to the followingdescription of FIGS. 2 through 5.

Referring now to the FIGS. 2 through 5, there is shown a representativeportion of the automatic loading machine 10. Platen 12 is asubstantially rectangular steel plate having a shallow groove or channel14 machined into the upper surface thereof to receive and direct ahorizontally displaceable primer transport member comprising a fiatmachined steel bar 16 and suitably secured thereto a steel slide block18. The transport member comprising bar 16 and block 18 operates toindividually meter percussiontype primers 24 from a supply representedby hollow vertical tube 26 to a work station which is displaced to theleft, as shown in FIG. 2, for example, of the supply, where the primersare assembled into cartridges as one of several steps which areautomatically carried out by the machine 10. The transport membercomprising bar 16 and block 18 is caused to be displaced horizontally,that is, from left to right in FIG. 2 in a cyclical fashion by drivemeans to be described.

The slide bar 16 has formed in the forward portion thereof, that is, theportion to the left in the drawing of FIG. 2 a vertically-orientedaperture 20 having a rounded interior peripheral lip 22 to serve as ametering receptacle for primers 24 which are stacked vertically on topof one another in the supply tube 26. The tube 26 is supported by means,not shown, relative to the lower platen 12 so as to provide registrationbetween the discharge opening at the bottom of the tube 26 and theaperture 20 in the slide bar 16 during each cyclical displacement of theslide bar relative to the platen 12. :In the apparatus 10 of FIG. 1, theaperture 20 is aligned with the opening in the primer tube 26 as theslide bar is caused to be traversed to the right-handmost position, thisposition being illustrated in FIG. 2.

In a specific embodiment, the primers 24 are approximately 0.165 inch indiameter and 0.117 inch in vertical height or thickness. Accordingly,the aperture 20 in the slide bar 16 is made slightly oversize to have adiameter of 0.179 inch and a vertical height or thickness of 0.134 inch.The rounded lip 22 together with the slightly rounded edge configurationof the typical primer 24 provides compensation for the 0.017 differencein the height or thickness of the aperture 20 and primer 24 which, aswill be apparent, permits the second primer up in the stack to fallslightly into the aperture 20. As the slide bar 16 is displaced to theleft, as shown in FIG. 2, the entire stack of primers 24 is, thus,caused to rise the 0.017 inch necessary to provide clearance for theupper surface of the slide bar 16. In addition, the slight verticaloversize of the aperture 20 in the slide bar 16 compensates for anyrough edges or small amounts of particle accumulation which may occur inthe primer receptacle defined by the aperture 20, thus, to reduce thepossibility of a jam occurring at the primer acceptance position shownin FIG. 2.

The minimization of foreign particle collection is significantlyenhanced in the apparatus 10 of FIGS. 2 and 3 by the provision of avacuum apparatus including a fitting 28 which is threaded into a tappedportion of a vertical channel 30 in the lower platen 12, the fittingbeing connected to a pipe 32 which in turn is connected to a vacuum pump34. As shown in FIG. 2, the channel 30 is aligned with the primer supplytube 26 and, thus, when the slide bar 16 is in the primer pick-upposition shown in FIG. 2 the channel 30 is also aligned with theaperture 20 in the slide bar 16. Channel 30 is about inch in diameter,too small to permit a primer to fall through. By causing an air flow thesupply area to the pump 34, any excess primer powder which is inherentlycarried by the primers 24 is swept away rather than permitted toaccumulate in the primer pick-up area where if present in sufiicientquantity a danger of explosion could result. In addition, the vacuumaction clears the primer pick-up area of other foreign particles, suchas dirt which might interfere with the proper seating of the primers 24into the aperture 20 and which could, thus, cause an interruption ofautomatic loading operation. Finally, the vacuum force tends to draw thelowermost primer 24 into aperture 20, assisting the gravity feed.

From the primer pick-up position shown in FIG. 2 wherein gravity causesthe lowermost primer 24 in the supply tube 26 to fall into the aperture20 in the slide bar 16, the drive means to be described causes the slidebar 16 to move forwardly, that is, to the position illustrated in FIG.3. This position aligns aperture 20 with a work station defined by areceptacle 36 in the lower platen 12. The drive means is such as tocause the aperture 20 and the slide bar 16 to be in register with thereceptacle 36 during each cyclical displacement of the slide bar, thus,to permit the primer 24 being carried forward by the slide bar to fallinto the receptacle 36. According to typical machine operation, theslide bar 16 is then drawn back and a shuttle bar 62 captures acartridge, casing, or shell to be assembled and mechanical means notshown, cause the primer which has been placed in the receptacle 36 to beassembled into the cartridge, casing, or shell in a suitable manner.Typically, this involves the application of a blunt pin upwardly throughthe small opening which connects with the receptacle 26, as shown inFIGS. 2 and 3.

Describing now the drive means for effecting the cyclical displacementof the slide bar 16 as well as apparatus associated therewith, themachine comprises an upper platen assembly 38 which is mounted on one ormore guide pins 40 which in turn are suitably anchored to the lowerplaten 12. The assembly 38 is, thus, mounted for cyclical verticaldisplacement to effect various automatic loading operations, such asmetering primers, powder and shot, crimping, and so forth. The upperplaten assembly 38 is caused to be cyclically vertically displaced by amotor 42 and a suitable crankshaft arrangement, these elements beingpreferably disposed within base 11. Upper platen assembly 38 carries onthe righthand edge thereof, as shown in FIGS. 2 and 3, a dependingvertical cam 44 which programs the cyclical horizontal displacements ofthe slide bar 16 to be synchronized mechanically with the verticaldisplacements of the upper platen assembly 38. The program surface ofcam 44 is on the rear, that is, the righthand edge of the cam, as shownin FIGS. 2 and 3, and includes two vertical portions 46 and 48 joined byan inclined or angulated surface 50. The surface of cam 44 is contactedby a roller-type follower 52 on the slide block 18. The surface portion46 of cam 44 represents the dwell of the slide bar 16 in the primerdischarge position of FIG. 3 wherein aperture 20 is in register withreceptacle 36. The surface portion 48 of cam 44 represents the primerpick-up position of slide block 16 wherein the aperture 20 is inregister with the supply tube 26 and the vacuum channel 30, as shown inFIG. 2. The inclined surface portion 50 of cam 44 represents thedisplacement or travel of the slide bar 16 between these two dwellpositions.

As is best illustrated in FIGS. 2 and 3, the roller follower 52 contactsonly one side of the cam 44, thus, the slide bar 16 and the slide block18 are positively driven by cam 44 only from the work station defined byreceptacle 36 to the supply point defined by the position of the supplytube 26. To drive the slide bar 16 in the oppositedirection, that is,from the supply point to the work station with the primer being carriedinto place, an anchor block 54 is mounted on the lower platen 12 bysuitable fastener means, such as machine screws, and carries a forwardlyextending and horizontally oriented guide rod 56 which extends into adeep hole 58 in the slide block 18. A spring 60 is disposed in the hole58 and about the rod 56 so as to abut against the anchor block 54 tobias the slide block 18 to the left, as shown in FIGS. 2 and 3. Thisresiliently biases the follower 52 against the program surface of cam 44such that only the force of the spring 56 actually drives the slide bar16 from the supply point to the work station. This has the advantage ofeliminating any positive machine drive on the slide bar 16 during thetravel of the slide bar to the work station, thus, minimizing if notsubstantially eliminating the possibility of applying the full pressuregenerated by the force of motor 42 on the slide bar 16 to a primer 24which may have been caused to occupy an interfering and, thus, jammingrelationship with respect to the slide bar 16. For example, itoccasionally occurs in the reloading of previously-used ammunition casesthat the step of removing the previously-used primer is incomplete andeffective only to remove the center of the primer leaving the outer wallthereof in place. This outer wall then occasionally stays in themetering area such that the next primer 24 may be placed into a jammedposition. The location of a primer 24 half-way, for example, into theaperture 20 causes a shearing pressure to be applied to that primer whenthe slide bar 16 begins its forward travel, the primer being squeezedbetween the rear surface of the aperture 20 and the front inner surfaceof the supply tube 26. Under these circumstances, the explosion of thesingle primer is quite possibly effective to discharge all of theprimers stacked up vertically in the supply tube 26, thus, causing anexplosion of possibly lethal proportions. The spring 60, thus, producesa resilient, rather than positive, drive of the slide block 16 towardthe work station, the tension of the spring being selected to besubstantially less than that which can trigger a primer under ordinarycircumstances. The positive drive of the slide bar 16 from the workstation back to the slide point is satisfactory since, at this point, noprimer can occupy an interfering and, thus, jamming position in themachine 10.

The machine 10 comprises an additional control means for interruptingthe application of electrical energy to the motive power source 42 inthe event the slide bar 16 and the slide block 18 associated therewithfails to traverse forwardly, that is, to the left as shown in FIGS. 2and 3 as the upper platen assembly 38 descends. Such an occurrence isindicative of a jam in the primer metering apparatus and, thus, causes atemporary shutdown of the automatic loading operation.

This control means is illustrated in FIGS. 2 through 5 and includes amechanically operated switch 64 which is mounted on the upper platenassembly 38 by means of a bracket 66 such that the switch 64 isvertically and cyclically displaced along with the upper platen assembly38. Switch 64 may be of the type commonly identified as a Microswitchand is provided with a rotatable control element 68 which is biaseddownwardly such that the switch 64 resides in a normally-closedcondition. However, control element 68 is angularly displaceable by anexternally-applied force to open the switch 64. Switch 64 is in turnconnected to a relay 70 which constitutes the main conductance pathbetween the volt AC supply and the motor 42.

Switch 64 is mounted on the back of the upper platen assembly 38, asshown in FIGS. 2 and 3, and vertically above the righthand end of theslide block 18, as shown in FIGS. 4 and 5. Accordingly, a straightvertical displacement of the upper platen assembly 38 and the switch 64,as is required by the guide pins 40, displaces the control element 68along a path which intersects the path of occupancy of the control block18 during its cyclical displacement. However, if the spring 60 iseffective to bias the roller follower 52 against the program surface ofcam 44, the inclined area 50 permits the slide block 18 to move out ofthe way of the control element 68 as the upper platen assembly 38descends. Thus, under normal operating conditions the control element 68remains downwardly biased. The switch 64 remains closed; the relay 70remains closed; and power is continuously applied to the motor 42 tocontinue the automatic loading operation.

However, if a primer jam occurs in such a fashion as to prevent theforward displacement, that is, from right to left, as shown in FIGS. 2and 3, of the slide bar 16 and the slide block 18 which is securedthereto, the downward displacement of the upper platen assembly 38carries the control element 68 of switch 64 directly into the areaoccupied by the slide block 18 as shown in FIG. 5. This torques thecontrol element '68, opening the switch 64 and, in turn, opening relay70. This interrupts the conductance of electrical energy to the motor 42shutting down the operation of machine 10 until the jam condition hasbeen cleared up and the relay 70 reset. A manual bypass for relay 70 maybe included so that the motor 42 can be advanced in small incrementsafter the jammed condition has been cleared up or in the process ofclearing up the primer jam. In the machine art, this is known as a jogand will not be described in detail.

In summary, it has been demonstrated that an automatic loading machinefor ammunition may be provided with a cyclically translating transportmember for metering primers between a supply area and a work station,the drive means for this transport member being such as to provide aresilient, relatively low force drive from the supply to the workstation and a positive relatively high force drive from the work stationback to the supply. This has the advantage of decreasing, if noteliminating the likelihood of inadvertent and spurious detonation of apressure-sensitive primer while undergoing automatic loading in themachine. In addition, the likelihood of such spurious detonation isfurther reduced by means of a vacuum cleaning arrangement which clearsthe metering receptacle in the slide bar. Finally, an interruption ofthe application of power to the motive power source of the machine iscaused in the event the primer transport mechanism is found to be out ofdisplacement synchronism with the drive means or with a machine partwith which it normally displaces in synchronism.

It is to be understood that the foregoing description is illustrative innature and is not to be construed in a limiting sense.

The embodiments of the invention in which an exclusive property orprivilege is claimed are defined as follows:

1. Primer transport apparatus for loading machines comprising: supportmeans, a transport member displaceable relative to the support means forcyclically transporting primers from a primer supply to a work station,drive means for resiliently urging the transport member toward the workstation but positively driving the member from the work station backtoward the supply, and means responsive to a failure of said transportmember to move away from said primer supply for shutting 01f said drivemeans.

2. Apparatus as defined in claim 1 wherein the transport member includesa portion defining a primer receptacle which is placed in communicationwith the supply during each cylical displacement of the member toreceive a single primer therein.

3. Apparatus as defined in claim 2 wherein the trans port memberincludes a flat bar of rigid material displaceable across and in contactwith the support means, the receptacle defining a vertically extendingaperture in the bar of a depth slightly greater than the depth of aprimer and having a rounded peripheral tip.

4. Apparatus as defined in claim 2 including a supply tube disposed overthe transport member for containing a vertically stacked array ofprimers, the tube having an open discharge aperture which is in registerwith the receptacle during each cyclical displacement of the member.

5. Apparatus as defined in claim 1 wherein the drive means comprisesanchor means on the support means, a displaceable cam for programmingthe displacement of the transport member relative to the support means,spring means for resiliently biasing the transport member against thecam and relative to the anchor means during travel of the member towardthe work station, and follower means on the member and engaging the camfor positively driving the member away from the work station.

6. Apparatus as defined in claim 5 including an upper platen verticallydisplaceable relative to the support means, the cam being carried by theupper platen for displacement therewith.

7. Apparatus as defined in claim 6 wherein the cam has thereon a surfacehaving first and second vertical portions representing dwells of thetransport member at the supply and work station respectively, and aninclined portion joining the first and second portions for causingdisplacement of the transport member.

8. Apparatus as defined in claim 7 including a follower on the member,the drive means including a spring for resiliently biasing the followeragainst the surface to provide the cyclical displacement of the member.

9. Apparatus as defined in claim 1 including a motive power source forthe drive means, said means responsive to failure of said transportmember to move including control means for interrupting the operation ofthe source whenever the transport member fails to move toward the workstation under the resilient urging of said drive means.

10. Apparatus as defined in claim 9 wherein the transport memberincludes a bar slideably displaceable over the support means, and thedrive means includes a cyclically, vertically displaceable assembly, acam carried by the assembly for synchronizing the displacement of thebar therewith, a follower on the bar and a spring biasing the followeragainst the cam, the control means comprising a switch carried by theassembly and having a control element for controlling the electricalcondition thereof, the control element being disposed to contact thetransport member only if the bar fails to slide to the work station asthe assembly descends.

11. Apparatus as defined in claim 1 including a primer receptacle in thetransport member, and vacuum means for exerting a pneumatic forcetending to draw primers into the receptacle and to clear the receptacleof foreign matter.

12. Apparatus as defined in claim 11 wherein the vacuum means includesan aperture in the support means in vertical register with the supply, avacuum pump in communication with the aperture such that as thereceptacle of the transport member lines up between the aperture and thesupply, a primer is drawn into the receptacle by said pneumatic force,the aperture being of such size as to prevent passage therethrough of aprimer.

References Cited UNITED STATES PATENTS 3,036,488 5/1962 Bihler 86263,580,128 5/1971 Leich 8631 3,153,976 10/1964 Linder 8626 3,253,4965/1966 Beach et al. 8626 3,057,247 10/ 1962 Behrens 8631 2,829,5534/1958 Twidwell 8623 X 3,157,086 11/1964 Bachhuber 8631 X 472,990 4/1892 Gallup 8625 BENJAMIN A. BO'RCHELT, Primary Examiner H. TUDOR,Assistant Examiner US. Cl. X.R. 8620

